The present invention relates generally to mufflers used to deaden sound in exhaust gas streams generated by internal combustion engines, and more particularly, to a modular muffler that is quickly and easily adapted for use with a wide variety engines. The muffler has a dimensionally standardized body with end portions that may receive any of a number of adaptor end plates provided with various inlet and outlet configurations.
Motor vehicles, whether they be automobiles, light trucks, vans, heavy-duty trucks, buses, etc., are most often powered by various types of internal combustion engines. These types of internal combustion engines, and the many different manufacturers models thereof, vary considerably in terms of their design, operating and performance characteristics, and consequently, they typically result in the production, distribution, storage and use of a widely divergent array of muffler systems that are tailor-made to provide not only a desired amount of exhaust gas noise attenuation, but also a suitable level of exhaust system back pressure for each engine model and type.
Attendant with such diversity of systems is increased cost at virtually every commercial stage. Manufacturing expense is boosted by the need to have multiple types of tooling to produce and assemble a multiplicity of perhaps similar yet different sized muffler parts. Storage and inventory cost is inflated by the requirement that a large number of stock keeping units (SKU""s) must be assigned, recorded and maintained, considerable floor space must be set aside for storage, and complex systems must be acquired and maintained to monitor and replenish supplies of the systems. Shipping and handling outlays can also be considerable due to the need to ship order sizes which are less than economic order quantities.
In view of the foregoing a need exists to provide a modular muffler construction that not only is highly versatile and thus capable of being used effectively with a variety of engine types and models, but also is more economical to fabricate, acquire, store and install.
The present invention is a modular muffler construction that may be quickly and easily adapted for use with a wide variety of internal combustion engine types and manufacturers models thereof. The muffler construction generally comprises a universally-sized, central body member provided with a pair of longitudinally separated open ends. Each open end is capable of receiving an end adaptor plate, a body adaptor, an end cap and/or a vehicle adapter. The body member preferably will be elongated along its central longitudinal axis. It will internally include a pair of diagonally arranged perforated tubes that extend from a first end chamber situated at, and defining one of the open ends to a second end chamber located at and defining the other of the open ends of the body. The body member will further include a plurality of layers of sound deadening material that extend lengthwise along the interior of the body and inwardly toward the perforated tubes so as to wrap the tubes in a noise attenuating blanket. The end adaptor plate may be provided with one or more orifices through which exhaust gas may flow. The orifice(s) may be of any desired diameter and/or may be positioned in any of a number of different locations on the plate. The end adaptor plates, once received within an open body member end, may also be adjusted inwardly and outwardly relative to the end in order to vary the internal volume of the body member.
More than one of the muffler body members may be arranged end-to-end, and joined together either by direct contact between their ends or by linking the ends via a body adaptor. The body adaptor may be provided with a deflector plate to facilitate exhaust gas flow between the body members, and it may alternatively be utilized not as a means to join body members, but to install flow restrictors to create turbulence to control flow and sound, and to provide an exhaust gas expansion chamber on one or both ends of a sole body member.
The end cap preferably will be a dome-shaped structure, which, when applied to one of the open ends of the body member, will permit exhaust gas that has entered the body member from the opposite end and traveled to the end cap to be diverted by 180 degrees and caused to journey back through the body member and to exit the muffler from the end through which gained entry. Alternatively, the end cap may be partially dome-shaped and additionally include a tubular extension that allows at least some of the exhaust gas to exit from the end cap.
The vehicle adaptor is a duct-like member that, in addition to having a radially outward extending flange portion for receipt by an open end of the body member, preferably has an outer end portion that is cylindrically shaped and a intermediate portion that is semi-hyperboloid shaped. The vehicle adaptor permits the muffler body member to be used with more than one category of vehicle. By way of example, the vehicle adaptor makes it possible for the one or more of the muffler body members to be applied to larger diameter components (pipes and pipe-like inlets and outlets) of the exhaust systems of heavy duty trucks in addition to smaller diameter components of the exhaust systems of automobiles, light trucks, vans, and the like.
The modular muffler construction can further include one or more spark arresters, past which the exhaust gas is caused to flow. Preferably, the spark arrester(s) will be contained within the second end chamber of the body member and be secured to an end adaptor plate and at an exhaust gas exit orifice provided therein. Inclusion of one or more spark arresters in such manner has been found to be particularly useful for off-road vehicle applications.
The modular muffler may also be constructed so that elongated, exhaust gas carrying tubes extend from the outboard side of an end adaptor plate, through the plate orifices, into the end chamber of the body member and toward the diagonally arranged tubes within the central portion of the body member. The elongated, exhaust gas carrying tubes can be louvered and/or perforated to obtain desired flow and sound levels.
Given the above described modular muffler construction it should be evident that the present invention has as one of its objectives significantly reducing the number and types of different muffler systems and their constituent parts that have to be produced. As previously suggested, achievement of this objective can be expected to yield a number of advantages including, but not limited to, assignment, maintaining and monitoring of fewer SKU""s, lowering production tooling costs and storage space allocations, paring distribution expenses and providing vehicle manufacturing and repair facilities with the ability to quickly and easily assemble muffler systems for a multitude of configurations. These advantages and others will become more readily apparent from a review of the following detailed description of the invention and of the drawings attached hereto.